1. Field of the Invention
The invention relates to a fuel injection device, in particular an injector, for internal combustion engines, having a base body, having an injection housing, having a fastening device which includes at least one lock nut with an annular land and an annular shoulder on the injection housing and which braces the injection housing axially against the base body, having a fuel inlet, and having at least one valve element.
2. Description of the Prior Art
One fuel injection device of the type with which this invention is concerned is known from German Patent Disclosure DE 197 29 843 A1. This reference shows a fuel injection valve for internal combustion engines which has a lock nut that rests with an inner, conically embodied annular land on an annular shoulder of an injection housing. In this way, the injection housing is braced against the base body. The annular shoulder, on its side toward the annular land, is embodied in curved form, in such a way that at a predetermined spacing from the longitudinal axis of the fuel injection device, a support point extending annularly all the way around, on which the conical annular land rests in the installed state, is created.
The object of the present invention is, in a fuel injection device of the type defined at the outset, to improve the seal between the injection housing and the base body. Moreover, the deviations in the injection quantity are to be reduced. In addition, because of the uniform axial bracing, wear of the nozzle needle guide and at the nozzle needle seat are reduced.
This object is attained, in a fuel injection device of the type defined at the outset, by providing that the fastening device has at least one annular face which is oriented toward the annular land of the lock nut and is curved convexly in the manner of a spherical-segmental face.